P1575: TIKSAGEVIMAB/TSILGAVIMAB: EXPERIENCE OF USE FOR PRE-EXPOSURE PROPHYLAXIS OF COVID-19 IN ADULT PATIENTS WITH ONCOHEMATOLOGICAL DISEASES
Authors: Daria Chebykina, Sergey Voloshin, Marina Zenina, Alexey Kuvshinov
Journal: HemaSphere (2023)

Topic: 30. Infections in hematology (incl. supportive care/therapy) Background: Patients with oncohematologicaldiseases belong to a high risk group for infection and the development of severe complications after COVID-19 because of the character of the primary disease and features of the treatment they undergo. The optimal method of long-term pre-exposure prophylaxis for immunocompromised patients is use of neutralizing monoclonal antibodies (MABs) to COVID-19. Currentlya combination of MABsbinding to the spike protein COVID-19 is known - tixagevimab/cilgavimab. Aims: To evaluate the effectiveness and safety of use MABs for oncohematological diseases patients. Methods: 53 oncohematological diseases patients are included into the research. The median age is 58 (21-76), women dominated in the study group – 56,6% (n=30). Median follow-up after drug administration was 5,2 (4,2 – 7,1) months. 30.18% (n=16) of patients were vaccinated before MABs administration. Spitnik V was used to vaccinate 26% (n=14) of patients and Sputnik Light was used to vaccinate 4,18% (n=2) of patients. 75% (n=40) of patients experienced COVID-19 before administration tixagevimab/cilgavimab, three of them experienced it twice. 72 % (n=38) of patients were undergoing induction and anti-relapse therapy when MABs was administered, and autologous bone marrow transplant was performed for 18,9% (n=10) of patients. Results: 6 % (n=3) of patients were diagnosed withCOVID-19 within 6 months after MABs introduction. All the patients infected after undergoing pre-exposure prophylaxis had a mild infection. During factor analysis the age of patients (p=0.8), previous vaccination (p=0.4), type of vaccine (p=0.62), chemotherapy (p≥0.5) didn’t influence the probability of developing COVID after the administration of MABs. The fact of vaccination before the administration of the MABs did not have a statistically significant effect on the effectiveness of pre-exposure prophylaxis, however, there was a tendency of decrease of the development of repeated episodes of COVID-19 after vaccination: in vaccinated patients, the frequency of repeated episodes of coronavirus infection was 6.2% vs 15.4% in unvaccinated patients (p=0.6). While evaluating the adverse events profile of tixagevimab/cilgavimab. Episodes of arterial hypertension in three patients, the development of febrile fever in two patients, nausea in three patients should be distinguished. The rest adverse events were of a single character and had a mild severity according to the classification NCI CTCAE v5.0. An adequate survival analysis could not be carried out, because 1 (1.9%) fatal case was registeredin our study, associated with an infectious complication during the period of post cytostatic pancytopenia, unrelated to COVID-19. Summary/Conclusion: According to our data, the use of tixagevimab/cilgavimab as a pre-contact prophylaxis of COVID-19 is not associated with loss/ deterioration of hematological response after administration of the drug. Isolated non-hematological adverse events of mild severity have been reported. There were no episodes of severe COVID-19 after administration of tixagevimab/cilgavimab. In prospect, the observation of this group of patients will be continue with a subsequent evaluation of immunity to COVID-19. Keywords: COVID-19